1. Technical Field
The present invention relates to a method of preparing 5-acetoxymethylfurfural, and, more particularly, to a method of preparing 5-acetoxymethylfurfural using an alkylammonium acetate salt, which is economical and has high reaction efficiency.
2. Description of the Related Art
Due to the exhaustion of traditional energy sources together with the increase of world-wide energy demand, the development of alternative energy sources is currently receiving much attention. Among alternative energy sources, biomass has attracted considerable attention as a quantitative biological resource that can be regenerated, as shown in the alternative energy development project “Production of fuel from biomass” conducted by U.S. Department of Energy (DOE). 5-hydroxymethylfurfural (HMF) is a biomass-derived material that can replace petrochemical-based compounds whose production and usage have already been established, and, to date, research into this 5-hydroxymethylfurfural has been conducted.
It was reported that HMF is generally synthesized by the dehydration reaction of hexose in the presence of a metal catalyst. However, this synthesis method has been difficult to commercialize because of a difficulty in separation attributable to the usage of a specific reaction solvent, an anhydrous condition attributable to the usage of a metal catalyst, reduction of yield, and the like. As a method for solving the above problem, there was proposed a method of synthesizing 5-chloromethylfurfural (CMF) which is a precursor of HMF and derivatives thereof. Such synthesized products have relatively high stability and are obtained in a high yield (Chem. Sus. Chem. 2009, 2, 859; Angew. Chem. Int. Ed. 2008, 47, 7924).
5-acetoxymethylfurfural (AcHMF) is a main target material in the derivation reaction of HMF using CMF as a starting material. Since AcHMF is structurally similar to HMF, it has high reactivity, high multifunctionality and high lipophilicity and is comparatively stable, so it can replace HMF at the time of synthesis of furan-based monomers.
Meanwhile, a method of synthesizing AcHMF from 5-chloromethylfurfural (CMF) using acetic acid and inorganic bases was reported in the patent document (US2008/221205 A1). However, this method is problematic in that it has low practicality because of its low production yield.
Therefore, if an efficient AcHMF preparation method is developed, a mass-production process can be equipped based on the method and low-priced raw materials can be sufficiently supplied, therefore the demand for AcHMF as an industrial product will expand.